How many EVEN 5-digit numbers can be made from the digits 2, 4, 5, 6, 7, 8, and 9?

How many four-digit even numbers are possible if the leftmost digit cannot be zero? Repetition is allowed.

How many different license plates are possible if 2 uppercase letters are followed by 4 digits and the first digit cannot be zero?

The superintendent of a large school district, having once had a course in probability and statistics, believes that the number of teachers absent on any given day has a Poisson distribution with parameter u. Use the accompanying data on absences for 50 days to obtain a 95% large-sample CI for μ. Number of absences 012 3 4 5 6 Frequency 1 4 8 10 8 6 6 3 2 1 1 [Hint: The mean and variance of a Poisson variable both equal μ, so X Z = μ μ/n 7 8 9 10 has approximately a standard normal distribution. Now proceed as in the derivation of the interval for p by making a probability statement (with probability 1 - a) and solving the resulting inequalities for u.] (Round your answers to two decimal places.) 5.66 X 4.42 × )